INTRODUCTION: The electrocardiogram (ECG) is often used to identify which hyperkalemic patients are at risk for adverse events. However, there is a paucity of evidence to support this practice. This study analyzes the association between specific hyperkalemic ECG abnormalities and the development of short-term adverse events in patients with severe hyperkalemia. METHODS: We collected records of all adult patients with potassium (K+) ≥6.5 mEq/L in the hospital laboratory database from August 15, 2010, through January 30, 2015...

We report a case of junctional rhythm that occurred both preoperatively and later during a portion of general anesthesia. A 19-year-old woman was scheduled to undergo bilateral sagittal split ramus osteotomy after being diagnosed with a jaw deformity. Preoperative electrocardiography (ECG) revealed a junctional rhythm with a slow heart rate (HR). At 90 minutes after anesthesia induction, local anesthesia with 10 mL of 1% lidocaine and 1:100,000 adrenaline was administered. A junctional rhythm appeared 15 minutes after the local anesthesia...

We present here a 45-year-old male with no past medical problem who presented with palpitations. He was found to have supraventricular tachycardia intractable to medical therapy. Later his rhythm converted to junctional tachycardia. Further workup revealed hemochromatosis to be primary etiology causing the arrhythmia. The low index of suspicion for additional workup is key to diagnosis and successful outcome.

The atrioventricular junction has a central role in electrophysiology, responsible for reentrant and automatic forms of supraventricular tachycardia. During atrioventricular nodal reentry tachycardia, the circuit involves 2 electrophysiologically separate pathways located in the vicinity of the atrioventricular node. Atrioventricular reentry tachycardia is caused by the presence of an accessory pathway located almost anywhere along the atrioventricular groove; the macroreentrant circuit involves the atrioventricular node, the accessory pathway and necessarily portions of atria and ventricles...

Although, acquired amusia is a common deficit following stroke, relatively little is still known about its precise neural basis, let alone to its recovery. Recently, we performed a voxel-based lesion-symptom mapping (VLSM) and morphometry (VBM) study which revealed a right lateralized lesion pattern, and longitudinal gray matter volume (GMV) and white matter volume (WMV) changes that were specifically associated with acquired amusia after stroke. In the present study, using a larger sample of stroke patients (N = 90), we aimed to replicate and extend the previous structural findings as well as to determine the lesion patterns and volumetric changes associated with amusia recovery...

Motoneurons are traditionally viewed as the output of the spinal cord that do not influence locomotor rhythmogenesis. We assessed the role of motoneuron firing during ongoing locomotor-like activity in neonatal mice expressing archaerhopsin-3 (Arch), halorhodopsin (eNpHR), or channelrhodopsin-2 (ChR2) in Choline acetyltransferase neurons (ChAT(+)) or Arch in LIM-homeodomain transcription factor Isl1(+) neurons. Illumination of the lumbar cord in mice expressing eNpHR or Arch in ChAT(+) or Isl1(+) neurons, depressed motoneuron discharge, transiently decreased the frequency, and perturbed the phasing of the locomotor-like rhythm...

Aims: The significance and incidences of intraoperative arrhythmias occurring in the operating room (OR) in children with congenital heart disease (CHD) are unknown. Aims of this study were to determine incidences of intraoperative arrhythmias in children with CHD and to examine whether they are associated with persistent arrhythmias during follow-up. Methods and results: Continuous ECG recordings obtained from 134 consecutive paediatric CHD patients were manually examined from the moment the aortic cross-clamp (ACC) was removed [use of ACC and cardiopulmonary bypass (CPB)], when CPB was stopped (use of only CPB) or when the sternum was closed (no use of ACC and CPB) until departure from the OR...

In mammals, the master circadian clock resides in the suprachiasmatic nucleus (SCN). The SCN is characterized by robust circadian oscillations of clock gene expression and neuronal firing. The synchronization of circadian oscillations among individual cells in the SCN is attributed to intercellular coupling. Previous studies have shown that gap junctions, specifically those composed of connexin-36 (Cx36) subunits, are required for coupling of electrical firing among SCN neurons at a time scale of milliseconds...

The lifespan of Drosophilamelanogaster can be extended substantially by inducing reproductive dormancy (also known as diapause) by lowered temperature and short days. This increase of longevity is accompanied by lowered metabolism and increased stress tolerance. We ask here whether behavioral senescence is ameliorated during adult dormancy. To study this we kept flies for seven or more weeks in normal rearing conditions or in diapause conditions and compared to 1-week-old flies in different behavioral assays of sleep, negative geotaxis and exploratory walking...

Lithium is a commonly used drug in psychiatric practice. It is used in the treatment of depression and bipolar disorder. It has a narrow therapeutic index with documented adverse effects even near therapeutic levels. It has myriad of manifestations at toxic levels. The cardiovascular effects range from relatively benign ST-T wave changes to fatal arrhythmias. We describe a case of lithium toxicity which presented as a junctional rhythm and later showed a variety of manifestations such as complete heart block, atrial fibrillation, sinus bradycardia, and finally reverted to sinus rhythm at par with serum lithium levels...

OBJECTIVES: Catheter ablation for rhythm control has emerged as a successful therapeutic option for the treatment of atrial fibrillation (AF), though it has not been well studied in octogenarians. This study evaluates its safety in octogenarians in a community hospital and reviews the benefits of rhythm control. METHODS: Among 1,592 patients undergoing AF ablation, 84 octogenarian were identified. The primary outcome was normal sinus rhythm (NSR) on electrocardiogram at discharge...

Circadian rhythms are daily rhythms that regulate many biological processes - from gene transcription to behavior - and a disruption of these rhythms can lead to a myriad of health risks. Circadian rhythms are entrained by light, and their 24-h oscillation is maintained by a core molecular feedback loop composed of canonical circadian ("clock") genes and proteins. Different modulators help to maintain the proper rhythmicity of these genes and proteins, and one emerging modulator is dopamine. Dopamine has been shown to have circadian-like activities in the retina, olfactory bulb, striatum, midbrain, and hypothalamus, where it regulates, and is regulated by, clock genes in some of these areas...

A 66-year-old woman with palpitations was referred to our center for catheter ablation due to drug-refractory, common type atrioventricular nodal tachycardia (AVNRT). A selective slow pathway ablation was attempted. A fast junctional rhythm with transient ventriculoatrial block followed by transient prolongation of the A-H interval occurred immediately after the radiofrequency (RF) application at the coronary sinus ostium (CSOS) level. To assess the location of the fast pathway and His bundle, we sought to visualize the anatomy of the triangle of Koch (TOK) by three-dimensional computed tomography (CT)...

Our approach to the ablation of atrioventricular nodal reciprocating tachycardia (AVNRT), the most common supraventricular tachycardia, is as follows: We first attempt ablation in the right atrial posteroseptum anterior to the coronary sinus ostium with a 4-mm non-irrigated tip catheter. If ablation within the triangle of Koch is unsuccessful with radiofrequency (RF), we switch to cryoablation and target a more superior (mid septal) region. We also utilize cryoablation if RF ablation produces transient VA block (absence of retrograde conduction during junctional rhythm) or a fast junctional rhythm (<350 msec)...

INTRODUCTION: The cardiac sodium channel SCN5A regulates atrioventricular and ventricular depolarization as well as cardiac conduction. Patients with cardiac electrical abnormalities have an increased risk of sudden cardiac death (SCD) and cardio-embolic stroke. Optimal management of cardiac disease includes the understanding of association between the causative mutations and the clinical phenotype. A 12-lead electrocardiogram (ECG) is an easy and inexpensive tool for finding risk patients...

A 70-year-old man, who previously received a dual chamber pacemaker for paroxysmal AV block (Sorin Symphony DR 2550), was noted on telemetry to have multiple episodes of rapid ventricular pacing at approximately 120bpm. Evaluation of the telemetry strips revealed that all of the rapid ventricular pacing episodes were initiated by brief runs of escape junctional rhythm. Programmed bradycardia parameters were AAI SafeR with lower rate limit of 50bpm.

Central Pattern Generator (CPG) circuits are neural networks that generate rhythmic motor patterns. These circuits are typically built of half-center oscillator subcircuits with reciprocally inhibitory connections. Another common property in many CPGs is the remarkable rich spiking-bursting dynamics of their constituent cells, which balance robustness and flexibility to generate their joint coordinated rhythms. In this paper, we use conductance-based models and realistic connection topologies inspired by the crustacean pyloric CPG to address the study of asymmetry factors shaping CPG bursting rhythms...

Being able to imagine another person's experience and perspective of the world is a crucial human ability and recent reports suggest that humans "embody" another's viewpoint by mentally rotating their own body representation into the other's orientation. Our recent Magnetoencephalography (MEG) data further confirmed this notion of embodied perspective transformations and pinpointed the right posterior temporo-parietal junction (pTPJ) as the crucial hub in a distributed network oscillating at theta frequency (3-7 Hz)...